RESUMEN
The object of this study was to determine the allergenicity of goat milk (GM) and cow milk (CM) and that of their respective lactosera (GML and CML), by in vivo and in vitro assays. Two systemic tests for anaphylaxis were carried out in guinea pigs, the animals being sensitized orally with the 2 types of milk and lactosera. Sera were taken from the orbital sinus of the experimental animals at 0 and 22 d of the experiment to perform the serological study and the passive cutaneous anaphylaxis test. For the latter, the guinea pigs were sensitized passively with antibodies against the 4 antigen solutions. Enzyme-linked immunosorbent assay and Western blot were used to determine the specific antibodies of the isotypes immunoglobulin G1 and immunoglobulin G(Fc) developed against the same 4 antigen solutions. From these anaphylaxis and antibody-production tests, it was concluded that GM is hypoallergenic when compared with CM. The lactosera produced more closely grouped results, with values always below those of the corresponding milk. None of the proteins in the 4 immunizing solutions were identified as being their main allergen. These results show the hypoallergenicity of GM versus CM, and also that both casein and lactoserum proteins may be responsible for allergy in each case. To analyze the possibility of producing an innocuous food for those allergic to milk proteins, it would be of interest to identify the epitope(s) responsible for such allergenicity.
Asunto(s)
Sueros Inmunes/inmunología , Hipersensibilidad a la Leche/inmunología , Leche/inmunología , Anafilaxia/inmunología , Animales , Anticuerpos/sangre , Western Blotting , Bovinos , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Cabras , Cobayas , Sueros Inmunes/química , Leche/química , Proteínas de la Leche/química , Anafilaxis Cutánea Pasiva/inmunología , Péptidos/análisisRESUMEN
The aim of the present study was to estimate the prevalence of Cryptosporidium parvum infection in goats maintained under semi-extensive feeding conditions in the southeast of Spain. Four farms took part in the study. Samples were obtained during the autumn and spring kidding seasons. The goats were divided into three groups: group I (0-15 days), group II (> 15 days-2 months) and group III (> 2 months-9 years). Faecal specimens were concentrated and smears of the sediment (25 microl) were stained by the modified Ziehl-Neelsen acid fast technique. Parasite oocysts were identified in all the farms; of the 582 goats, 111 were found to have the parasite in their faeces, i.e. the prevalence was 19.1%. The frequency distributions of the Cryptosporidium oocyst counts according to the age categories were 10.4%, 13.4% and 25.2% for groups I, II and III respectively. With respect to the kidding season, nodifferences were found. The present study revealed the high prevalence of Cryptosporidium infection in goats in the studied zone.
Asunto(s)
Criptosporidiosis/veterinaria , Enfermedades de las Cabras/epidemiología , Animales , Cruzamiento , Criptosporidiosis/epidemiología , Cryptosporidium parvum , Femenino , Geografía , Enfermedades de las Cabras/parasitología , Enfermedades de las Cabras/fisiopatología , Cabras , Masculino , Prevalencia , Estaciones del Año , España/epidemiologíaRESUMEN
A study was carried out with 20 goats of the Malagueña breed, half with a high (HG) and half with a low (LG) genetic capability for alpha(S1)-casein (AS1-CN) synthesis, to determine whether the 2 different genotypes (that cause differences in goat milk composition) are related to differences in nutritional feed utilization. Among the 10 HG goats, 7 had BB and 3 had AB genotypes for AS1-CN, whereas there were 7 EF and 3 FF genotypes in the 10 LG goats. The goats were fed diets differing in crude protein content (13.6 vs. 17.7% dry matter for diets 1 and 2, respectively). For each genotype group, a balance trial was conducted with each of the 2 diets in a 2-period balanced changeover designed with half the animals consuming diet 1 and the other half diet 2, determining individual feed intake and the utilization of N and energy in the diets. Greater voluntary feed intake on a metabolic body weight basis among the HG goats was identified as the first possible cause of their milk production. The HG goats also had a greater level of feed utilization, on a metabolic body weight basis, for N and energy intake. Greater ratios of N balance/ digestible N, milk protein N/digestible N, milk energy/ digestible energy, and milk energy/ME were found for HG goats compared with LG. These effects appear to be dependent on the level of protein in the diet, indicating interactive effects. The greater N and energy utilization of HG versus LG goats may explain the differences in milk composition between the 2 genotype groups.
Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Caseínas/genética , Cabras/genética , Lactancia/metabolismo , Leche/química , Animales , Caseínas/análisis , Caseínas/biosíntesis , Estudios Cruzados , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía/fisiología , Femenino , Genotipo , Cabras/fisiología , Distribución AleatoriaRESUMEN
The beneficial effects of n-3 polyunsaturated fatty acids (PUFA) are well known, but their consumption in western countries is chronically insufficient, and so it is recommended that diets should be supplemented with a fat rich in these fatty acids. However, the effect of such diets on the energy expenditure remains a controversial question. Precise data concerning the effect of using under the same metabolizable energy intake, a diet non-supplemented or supplemented with a fat rich in n-3 PUFA are not available. This type of information was obtained using rats at weaning fed a diet supplemented or non-supplemented with 10% of fish oil. Between the 30th and 60th day after starting the experiment, the energy and protein balance was established by means of the comparative slaughter method. The blood levels of different metabolites were also determined. Although total thermogenesis did not vary between the two groups, consumption of the fish oil diet led to a lower level of thermogenesis associated with the oxidation of protein, and a higher one of that associated with the oxidation of fat. We conclude that the thermic effect of feeding is a combination of independent processes. Due to their specific metabolism, n-3 PUFA may be considered essential compounds to maintain the energy balance.
Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Metabolismo Energético/fisiología , Ácidos Grasos Omega-3/administración & dosificación , Termogénesis/efectos de los fármacos , Termogénesis/fisiología , Tejido Adiposo/metabolismo , Animales , Composición Corporal , Dieta , Grasas Insaturadas en la Dieta/metabolismo , Suplementos Dietéticos , Ingestión de Energía/fisiología , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos Omega-3/metabolismo , Masculino , Ratas , Ratas Wistar , DesteteRESUMEN
The objective of this study was to investigate the persistence of the effects of supplements after they were withdrawn. Two groups of 12 goats were maintained under semiextensive breeding conditions; they were fed indoors with a concentrate with alfalfa hay and olivetree leaves. Goats were in their sixth month of lactation at initiation of the study. During the first month of the trials, the concentrate supplied to the goats was either nonsupplemented (group 1) or supplemented with 9% polyunsaturated fatty acids (PUFA)-rich protected fat (group 2). After this period, the 2 groups were given the nonsupplemented until the average daily production of milk per animal within each group had decreased to 300 g or less. The fat supplementation supplied increased milk production and also improved fat and protein yield. These effects persisted after the supplement was withdrawn. The supplement, moreover, produced noticeable changes in the fatty acids profile of the milk fat, namely a reduction in the concentration of saturated fatty acids and an increase in that of PUFA. In contrast to the effects on milk production and on the yield of its main constituents, the effects on fat composition disappeared when the supplement was withdrawn.
Asunto(s)
Industria Lechera/métodos , Ácidos Grasos Insaturados/administración & dosificación , Cabras/fisiología , Lactancia/metabolismo , Leche/química , Leche/metabolismo , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Suplementos Dietéticos , Grasas/análisis , Ácidos Grasos Insaturados/análisis , Femenino , Cabras/metabolismo , Lactancia/efectos de los fármacos , Proteínas de la Leche/análisis , Distribución AleatoriaRESUMEN
Dietary fish oil has a beneficial effect on heart and some bacterial diseases and apart from other effects, some studies have revealed their ability to modulate the course of inflammatory and autoimmune diseases. The study here reported was designed to evaluate the possible influence of a fish oil supplement on the course of a Trichinella infection. Nutritional, parasitological and immunological parameters were analyzed. Two groups of 20 Wistar rats, one fed a standard diet and the other one a standard diet supplemented with fish oil, were infected with 1000 L1 larvae. Other two uninfected groups served as control. Results were as follows: fish oil diet intake and infection have, respectively, a positive and a negative effect on growth and food utilization. The negative effect is detected later in animals fed the fish oil diet. A reduction of 30.9 and 36.6% in the number of adult worms and L1 larvae, respectively, was observed in the fish oil group as compared to the standard diet group. Production of IFNgamma (Th1 response) and IL4 (Th2) response was measured in stimulated splenic cells. The fish oil diet increased both IFNgamma and IL4 levels. At 6 days after infection both IFNgamma and IL4 responses were detected, but at 36 days after infection only IL4 was detected in the standard group. The level of somatic and cuticular antibodies was not affected by the diet.
Asunto(s)
Ácidos Grasos Insaturados/farmacología , Aceites de Pescado/farmacología , Trichinella spiralis/inmunología , Triquinelosis/parasitología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Anticuerpos Antihelmínticos/sangre , Suplementos Dietéticos , Ingestión de Alimentos/efectos de los fármacos , Ácidos Grasos Insaturados/administración & dosificación , Aceites de Pescado/administración & dosificación , Interferón gamma/biosíntesis , Interleucina-4/biosíntesis , Masculino , Distribución Aleatoria , Ratas , Ratas Wistar/crecimiento & desarrollo , Ratas Wistar/inmunología , Trichinella spiralis/aislamiento & purificación , Triquinelosis/inmunologíaRESUMEN
To establish the effect of the nature of four different protein sources [fababeans, 27.8% crude protein (CP); sunflower meal, 41.7% CP; corn gluten feed, 18.8% CP; and cottonseed, 18.3% CP] on milk protein production by goats, the ruminal degradation of these feeds was studied as was the amino acid (AA) composition of the original material and that of the undegradable fractions of the protein sources. Four diets were designed; 20% of their protein was supplied by each of the different sources. Four groups of 5 Granadina goats were used to study the utilization of these diets for milk production. No significant differences were observed in dry matter intake or milk production. The milk produced by goats fed the diet containing sunflower meal had the lowest protein concentration; the highest milk protein concentration was observed for goats fed the diet containing corn gluten feed. From a multivariate analysis, it was deduced that the quickly degradable protein fraction in the rumen and the ruminally undegradable protein fraction were the components of the protein sources most directly related to the milk protein produced. Given the similar AA profiles of the undegradable fractions of the different protein sources, the possible supplementation achieved from these ruminally undegradable fractions must be established by the amount of protein supplied regardless of AA composition.
Asunto(s)
Aminoácidos/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Cabras/fisiología , Lactancia/fisiología , Leche/química , Aminoácidos/análisis , Animales , Peso Corporal , Aceite de Semillas de Algodón , Proteínas en la Dieta/análisis , Ingestión de Alimentos , Fabaceae , Femenino , Helianthus , Lactosa/análisis , Lípidos/análisis , Proteínas de la Leche/análisis , Plantas Medicinales , Rumen/metabolismo , Zea maysRESUMEN
An experiment was carried out with kid goats of the Granadina breed to identify the dietary factors affecting voluntary feed intake of the kid goat and those that additively could determine its body composition. The animals used were from birth to 61 d of age, fed ad lib. on different milk replacers containing 200, 240 and 280 g crude protein/kg DM and 200, 240 and 280 g fat/kg DM, thus giving nine dietary treatments. The utilization of the milk replacers and the animals' body composition were determined by balance and slaughter trials. There were significant positive effects of protein concentration of the milk replacers on component digestibilities, energy metabolizability, feed intake, empty-body weights, empty-body composition and protein and fat retention. The concentration of fat in the milk replacers also had a significant positive effect on the digestible and metabolizable energy concentration of the diets and on fat retention. The relationships existing between feed intake and diet composition (concentration of digestible protein, metabolizable energy and digestible protein:metabolizable energy ratio) as well as between empty-body composition or protein and fat retention and diet composition, were examined. From these it was deduced that feed intake was significantly influenced by the digestible protein concentration of the diets. The higher the digestible protein concentration the higher the feed intake up to a maximum digestible protein concentration value. As the digestible protein concentration of the diets was the dietary factor which significantly influenced feed intake, this also significantly influences the body composition and the protein and fat retention. The protein concentration of the feed at which metabolizable energy intake in these animals would be greatest was estimated to be 347 g/kg DM.
Asunto(s)
Alimentación Animal , Animales Recién Nacidos/metabolismo , Composición Corporal , Ingestión de Alimentos , Cabras/metabolismo , Análisis de Varianza , Animales , Grasas de la Dieta/metabolismo , Proteínas en la Dieta/metabolismo , MasculinoRESUMEN
Food intake, growth and protein utilization were studied in the Helix aspersa snail by means of a nutritional balance experiment. This was designed in a 5 x 11 factorial arrangement involving 5 diets of different protein content (10.0, 12.5, 15.0, 17.5 and 20.0%) and 11 animal ages (ranging over 15 to 180 days of age). Dietary protein content and animal age determined food intake and protein utilization. The variations of dry matter and protein intake rates, growth rates, growth efficiency factors and protein retention rates, depending on dietary protein content or animal age were in agreement with what happens in other animals. These results suggest that there is no need to use diets with more than 17.5% of crude protein in these animals.
Asunto(s)
Envejecimiento , Fenómenos Fisiológicos Nutricionales de los Animales , Proteínas en la Dieta/análisis , Ingestión de Alimentos , Caracoles Helix/fisiología , Animales , Caracoles Helix/crecimiento & desarrollo , Caracoles Helix/metabolismoRESUMEN
A study was carried out to examine the distribution of individual weights in Helix aspersa snails, the aims being to establish the best estimate of the ponderal growth and also to obtain a model growth curve. Four groups of 20 snails from the same clutch were analysed and kept under experimental conditions from birth up to 6 months. The variability of their individual weights within groups was studied by calculating the coefficients of variation every 15 days. At the same time, the assumed normal distribution of those weights was being tested. The coefficients of variation increased with age and the assumed normal distribution of individual weights had to be rejected. By means of a log transformation of the original data, a model growth curve was constructed, and was used to assess the possibility of estimating age from weight. We finally reached the conclusion that median weight, rather than the mean, would be a better measure of central tendency to use until it is possible to obtain selected populations. The difficulty of estimating age from weight is emphasized.